Auxiliary Heater Assembly Replacement for GMC Truck TopKick C-Series (Crew) C4/C5 2004

Tools Required

J 38185 Hose Clamp Pliers

1. Drain the engine coolant. Refer to Cooling System Draining and Filling .
2. Remove the hose clamps using the J 38185 .
3. Remove the rear bench seat. Refer to Rear Bench Seat Replacement .
4. Remove the auxiliary air outlet duct. Refer to Auxiliary Air Outlet Duct Replacement .
5. Remove the inlet and outlet auxiliary heater hoses from the auxiliary heater core.
6. Disconnect the auxiliary blower motor electrical connectors.
7. Disconnect the auxiliary blower motor resistor electrical connector.



8. Remove the screws (1) from the auxiliary heater assembly.
9. Remove the auxiliary heater assembly.

1. Install the auxiliary heater assembly.

Notice: Refer to Fastener Notice in the Preface section.




2. Install the auxiliary heater assembly retaining screws (1).

Tighten
Tighten the screws to 6 N·m (53 lb in).

3. Install the inlet and outlet auxiliary heater hoses to the auxiliary heater core.
4. Connect the auxiliary blower motor electrical connectors.
5. Connect the auxiliary blower motor resistor electrical connector.
6. Install the auxiliary air outlet duct. Refer to Auxiliary Air Outlet Duct Replacement .
7. Install the rear bench seat. Refer to Rear Bench Seat Replacement .
8. Install the auxiliary heater hose clamps using the J 38185 .
9. Fill the engine coolant. Refer to Cooling System Draining and Filling .